In prostate, erythrocytes, macrophages, platelets, bones, spleen, lungs, testes  Hydrolyzes phosphate  Enzyme dysregulation is associated with pathophysiological conditions e.g., prostatic acid phosphatase (cancer of prostate); tartrate-resistant acid phosphatase (abnormal bone resorption in osteoporosis)  Released by platelets during clotting. Binding to α2-macroglobulin leads to a reduction in its activity. This evidence concerns the gene ACP5 and prostate cancer.